Liquid smoke

Liquid smoke is a water-soluble yellow to red liquid used for flavoring.

Pyrolysis or thermal decomposition of wood in a low oxygen manner originated prehistorically to produce charcoal. Condensates of the vapors eventually were made and found useful as preservatives. The term wood vinegar for centuries was the popular term used to describe the water based condensates of wood smoke. Presumably, this is due to its utilization as food vinegar. Pliny the Elder recorded in one of his ten volumes of Natural History (Pliny) the use of wood vinegar as an embalming agent, declaring it superior to other treatments he used. Widely recognized as the father of chemical engineering, another naturalist documentarian Johann Rudolf Glauber outlined in Furni Novi Philosophici the methods to produce wood vinegar during charcoal making. Further, he described the use of the water insoluble tar fraction as a wood preservative and documented the freezing of the wood vinegar to concentrate it. Use of the French derivation, pyroligneous acid as a widely used term for wood vinegar emerged by 1788.

In the United States, the commercial distribution era of pyroligneous acid under a new term, liquid smoke that subsumed it began with E.H.Wright in 1895. Among Wright’s innovations were the standardization of the product, marketing and distribution. Wright’s liquid smoke and its modern-day successors have always been the subject of controversy about what they are and how they are made. But in 1913 Wright, prevailed in a federal misbranding case. Case judge Van Valkenburg wrote:

The Government, in trying to show that this is not smoke produced by combustion, has shown that it is produced in exactly the same kind of way that is stated on that label. The fact is that they have produced something here which they say has something of the flavor and properties similar to the curative properties of smoke; they get it out of wood and they get it by distillation and it turns out to be a substance like, if not exactly identical with pyroligneous acid. Well, nobody could be deceived into thinking it was specifically what the indictment charges they are being deceived with. It is a thing which is produced in such a manner from the art and methods employed in it, that the application of the term “smoke” to it seems to me to be apt or applicable instead of deceptive, and it does not deceive in the sense this statute implies.